1. Field of the Invention
This invention concerns an acceleration protective suit for the crew of high-performance aircraft. Such protective suits are available in some executions. They are classified into different type of suits—those which are supplied with air as compressed fluid, the so-called pneumatic protection suits, and suits which work based on the hydrostatic principle. The latter type either creates hydrostatic pressure directly on the person wearing the suit or it is provided with fluid veins that pass through mainly the local and instantaneous Z-axis and increase the internal pressure of the liquid column correspondingly by shortening the size of the protective suit. Together they are known simply as hydrostatic protection suits, although the fluid is not restricted to water alone.
2. Description of Prior Art
The invention especially involves a pneumatic protective suit. Few such protective suits are already known, for example from EP 1 755 948 which is closest to the prior art, furthermore there are also a few from US 2007/0289050, JP 2008 012 958 and DE 10 2007 053 236. Document WO 03/020586 A1 discloses a protective suit made of low-stretch material with double-walled compartments or bags. In the compartments, there are flexible plastic pipes laid. The air pipes are loadable with acceleration-dependent air pressures and thus stretchable as bubbles.
In such protective suits, the parts or regions of the body that are to be protected are surrounded by the protective suit or parts of it. The parts and regions of the body that are especially subject to extreme accelerations are thereby pressurised within such protective suits via bladders or pipes impinged with compressed air or gas subject to the accelerations in the instantaneous and local Z axis, known as Gz, by which the haemostatic pressure is counteracted. This is the overall object of such a protective suit.
The costs for an effective G-protection are still considerable with traditional suits and it is this invention's intention to reduce these costs with a new suit. This protective suit should be effective under all circumstances and in all conditions without special actions from the wearer, which are the case in traditional suits, especially in the border areas. Traditional protective suits are relatively heavy, stiff and the wearer sweats easily in it, which negatively impacts his mental state. Some suits may cause foot and arm pain for the wearer. With regard to breathing induced by excess pressure (Positive Pressure Breathing PPB), it is not proven from a medical perspective. Therefore, in addition to ensuring an absolutely reliable G-protection, i.e. reliably prevent a so-called G-lock, an improved G-protective suit should ensure this G-protection with low costs as far as possible and without making breathing under excess pressure a necessity. It should display its optimal effect in all situations without the user exerting any influence, i.e. without “Anti G Straining Manoeuvres” (AGSM) and as far as possible, it should offer high wearing comfort, similar to underclothes. It should thus prevent premature exhaustion of the wearer and reliably prevent aches. Moreover, it should automatically offer better protection, i.e. ensure adequate protection in case of a sudden drop in pressure and provide support for buoyancy in case of immersion in water. Optionally, it should include an active cooling device. The suit should be manufacturable as a standard suit and tailoring of such suits for each individual wearer, which was required previously, should be made obsolete.
This is brought about via a pressure regime where different parts of the body or the protective suit, with reaction forces, are supplied with different pressures. Different regions of the protective suit are developed differently for this purpose.
As the contact pressures of the protective suit covering vary on the body of the wearer, the bladders which cause these pressures should be designed in different sizes depending on the part of the body to be protected. As learned from the state of the art documents, the volumes of the bladders are proportionally large, which, in combination with the compressibility of air and allowing for the high onset rates of Gz, leads to a slow reaction of the protective suit.
The object of the present invention is to control the internal pressure of the body protected by the protective suit in accordance with the relative height of the body to be protected and in accordance with the effective local and instantaneous acceleration, Gz, and to also minimise the volume to be filled. The protective suit should furthermore be comfortable to wear without requiring an exact fit. It should be easy to wear and remove without need for breathing in excess pressure and it should provide a high level of protection and climate control.
Another object of this invention is to alleviate the venous return of the wearer due to rhythmic changing of this internal pressure.